When selecting lift vehicles, you will notice they list a weight capacity. But you must pay attention to more than just the weight capacity of a forklift to determine how much it can safely lift. Discover what role the load center plays in lifting capacity and how to calculate the amount your forklift can safely move. Once you know these concepts, you can select a forklift that will safely fit your facility’s needs.
Weight Classes for Forklifts
Forklifts fall into seven classifications based on their size, motor and tires. Within each classification are various types of lifts. The classes, according to the Occupational Health and Safety Administration (OSHA), are as follows:
- Class I: Electric motor rider trucks
- Class II: Electric motor narrow aisle rider trucks
- Class III: Hand trucks or electric motor hand trucks
- Class IV: Internal combustion engine forklifts with solid tires
- Class V: Internal combustion engine forklifts with pneumatic tires
Generally, electric vehicles are used indoors and those with internal combustion engines are for outdoor use. However, some larger facilities with adequate ventilation can use forklifts powered by internal combustion engines. Additionally, weight capacities for lifts with internal combustion engines tend to be higher than those with electric engines. Larger forklifts can also carry more than smaller vehicles.
For example, the small, three-wheel electric A25-30XNT from Hyster® has a weight capacity of 3,000 pounds. However, the larger, internal combustion engine-powered GP080-120VX from Yale® can carry up to 12,000 pounds. For safety, always consult the weight capacity guidelines on the truck before attempting to move a load.
How Much Can a Forklift Lift?
How much can a large forklift lift? Or how much can a small forklift lift? The answers to these questions and ones similar to them are more complicated than you might think. You must account for the lift truck’s maximum weight capacity and its load center.
Maximum Weight Capacity
The maximum weight capacity is the highest amount of weight the forklift can carry when the load’s center of gravity is placed over the load center on the forks. Also, if you have attachments on the forklifts, the carrying capacity is the lower value of maximum loads for the lift and attachment.
The load center relates to the load’s position and shape as used by manufacturers to calculate the highest weight capacity of a forklift. Commonly, the load center is 24 inches from the rear of the forks. Therefore, manufacturers calculate a container with even weight distribution and a center of gravity 24 inches from the rear of the forks on top of a pallet to test the load capacity.
If the load has a center of gravity farther away from the back of the forks than the load center, or if the load’s weight is unevenly distributed, the total carrying capacity of the forklift decreases. For instance, a 60-inch-long container with evenly distributed weight should have a load center of half its length — 30 inches.
How to Calculate Capacity of a Forklift
OSHA offers a field calculation to estimate the maximum carrying capacity of a forklift when its load is not at the load center. The calculation uses the ratio of the load center to the actual center and multiplies it by the maximum load capacity. Therefore, if you want to find out how much a 5K forklift can lift with a rated load center of 24 inches and an actual load center of 36 inches, you should do the following:
24 inches / 36 inches = 2/3
2/3 x 5,000 pounds = 3,333 pounds
Therefore, the maximum weight you can safely carry with a 5K forklift with a load center of 24 inches and an actual center of 36 inches is 3,333 pounds.
Another important calculation for forklifts to prevent tip-over is the load moment. The load moment can help you calculate the maximum carrying capacity for a forklift at a specific actual load center.
To calculate the load moment, take the maximum weight capacity and multiply it by the load center. For instance, if you want to know how much a 10K forklift can lift, you would first need to calculate the load moment based on the vehicle’s load center. If the load center is at 24 inches, multiply the load capacity by the load center:
10,000 x 24 = 240,000
Next, take this total and divide it by the center of the load you need to move. If you have a load that is 60 inches long, it has a load center of 30 inches. The calculation for the maximum weight of that load would be:
240,000 / 30 = 8,000 pounds
If you already know the physical dimensions of the loads you need to lift and want to see if your forklift can handle their weights, try this calculation using load moment to see if the container will exceed the maximum carrying capacity based on the load moment. Trying to carry more than this amount can cause the forklift to tip over.
How Much Forklift Capacity Do I Need?
The forklift capacity you need depends on the loads typically handled in your facility. For instance, if you need a compact solution for an indoor warehouse that will handle no more than 4,000 pounds, you could choose an electric three-wheel forklift like the J30-40XNT from Hyster. However, high-capacity forklifts, such as the H800-1050 HD/S from Hyster, can lift up to 105,000 pounds. Such high-capacity lifting works well for outdoor construction sites and other locations that require moving heavyweights.
Always consult the manufacturer’s data about the maximum weight capacity for a forklift and choose a lift vehicle that surpasses the typical weights your facility moves. By choosing a forklift that can move more than you need, you can account for reduced lifting capabilities if you must carry something without a load center that matches that of the truck.
Find a Forklift for Your Capacity Needs From Gregory Poole Lift Systems
When you better understand the weight capacities of forklifts and industrial-powered vehicles, choosing an option to fulfill your lifting needs is easier. Plus, selecting a forklift that can carry a higher weight capacity than you will need ensures your workers and those around them in the facility can stay safe.
Start the process of getting a new forklift for your warehouse or other facility today. View our range of forklifts from well-known brands such as Yale and Hyster at Gregory Poole Lift Systems.